Explanation on Nat

Static NAT
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-> In this type of nat each and every private IP should have exactly one public IP.
-> This type of nat is used for Internal servers of the private network which need to exposed to the public network

Dynamic NAT
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-> In this type of nat each and every private IP will have a pool of ip and each private ip will choose that ip from that pool
-> This type of NAT is used for when many number of clients will be used in the network.